package myreflect3;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

public class ReflectDemo2 {
    public static void main(String[] args) throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException, InstantiationException, IllegalAccessException {
        // T newInstance(Object... initargs):根据指定的构造方法创建对象
        // method1();
        // method2();
        // method3();
        // methid4();
    }

    private static void method4() throws ClassNotFoundException, NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException {
        // 获取一个私有的构造方法并创建对象
        // 1.获取class对象
        Class<?> clazz = Class.forName("myreflect3.Student");

        // 2.获取一个私有化的构造方法
        Constructor constructor = clazz.getDeclaredConstructor(String.class);

        // 被private修饰的成员,不能直接使用的
        // 如果用反射强行获取并使用,需要临时取消访问检查
        constructor.setAccessible(true);
        System.out.println((Student) constructor.newInstance("zhangsan"));
    }

    private static void method3() throws ClassNotFoundException, InstantiationException, IllegalAccessException {
        // 简写格式
        // 1.获取class对象
        Class<?> clazz = Class.forName("myreflect3.Student");
        System.out.println((Student) clazz.newInstance());
    }

    private static void method2() throws ClassNotFoundException, NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException {
        // 1.获取class对象
        Class<?> clazz = Class.forName("myreflect3.Student");

        // 2.获取构造方法对象
        Constructor<?> constructor = clazz.getConstructor();

        // 3.利用空参来创建student的对象
        System.out.println((Student) constructor.newInstance());
    }

    private static void method1() throws ClassNotFoundException, NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException {
        // 1.获取class对象
        Class<?> clazz = Class.forName("myreflect3.Student");

        // 2.获取构造方法对象
        Constructor<?> constructor = clazz.getConstructor(String.class, int.class);

        // 3.利用newInstance 创建student的对象
        // Student student = (Student) constructor.newInstance("zhangsan", 23);
        System.out.println((Student) constructor.newInstance("zhangsan", 23));
    }
}
